Piston ring-groove scraper and groove deepener



Oct. 29, 1935. c, D -STROMGREN 2,018,930

PISTON RING GROOVE SCRAPER AND GROOVE DEEPENER Filed Nov. 23, 1934' FIG.I

4 in van for Patented Oct. 29, 1935 I UNITED STATES PATENT OFFICE PISTON RING-GROOVE SCRAPER AND GROOVE DEEPENEB The invention is intended for use as a hand tool by mechanics when piston ring grooves,-particu'- larly in pistons for internal combustion engines, require the removal of accumulated carbon or an 5 increased depth in order to accommodate piston rings of increased thickness. In cutting or scraping tools, particularly those used in the metal arts and designated as hand tools, limitation of physical power and rigid relative holding means have 10 preventedfullest realization of the results desired for the time and energy spent with most tools available.

As explained and described herein it will be recognized that my particular application of a 15 semi-rigidly sustained cutting or scraping tool to the ring groove of an internal combustion engine piston and the improved predetermined relative aligning and holding means gives a less resistive material removal effect to rthe advanc- 20 ing cutting tool, and has less tendency to dig or gouge to uncuttable depth, than has heretofore been experienced with other forms of rigidly adjustable hand cutting or scraping ring groove tools.

25 The principal object of my invention is to provide a hand-scraping or cutting tool for internal combustion engine piston grooves that is adaptable through a range of different diametered pistons with different width ring grooves;

30 one that will scrape or cut rapidly as desired without digging or gouging and with the least possible efiort, effecting a smooth surface over which it has cut.

The details in the construction of certain pre- 35 ferred forms of my inventiontogether with other objects attending its production will be best understood fromthe following description and accompanying drawing which is chosen for illustrative purposes only:

40 Fig. 1 is an elevation of the device showing a piston In in position, preparatory to removing material from the ring groove II. To illustrate more clearly the position of the bar I with its goose neck I, a cutter 3, and ring groove II, the

45 piston I is shown on the line A A Fig. 2.

Fig. 2 is a plan of Fig. 1 showing the goose neck I of bar I and cutting tool 3 inserted in ring groove II of piston I0.

Fig. 3 is an elevation of the device showing the 60 cutter post in position for operation on larger sized pistons with spring I compressed.

Fig. 4 is an elevation of the device showing the cutter post close to the goose neck bar I with spring I extended. 5 Fig. 5 is an elevation 01' the device minus the spring I the device may be operated this way as hereinafter explained.

Fig. 6 is an elevation of the device minus the cutter post height settingspring 5; the device may be operated in this manner as hereinafter 5 explained.

Fig. '7 is a detail plan of the revolvable cutter 3 which is held on the post in any conventional manner; in this use the post is riveted over.

Fig. 8 is an elevation of Fig. 7.

Fig. 9 is a detail plan of cutter post 2, adjusting nut 4, and a broken view of the goose neck on bar I.

Fig. 10 is a detail end elevation of cutter post 2 with the adjusting nut 4 in half section, showing also a section of bar I inserted inslot I2 01 cutter post 2.

More particularly describing the invention as illustrated, the cutter 3 is revolvably mounted on post 2 so that any one of.the difierent width members thereon, sized to fit'standard grooves,

may be turned to contact and cutting position as shown in Figs. 1 and 2.

Variation of longitudinal position of cutter 3, for cutting the grooves of different sized pistons, is provided for by sliding movement of the post 2 on bar I on which cutter shaft 2 is slidably mounted. The bar I is made long enough to serve as a handle for operation of the device, which also gives added range of movement away from the goose neck when placing a piston to cutting position or in making room for its removal.

It is obvious that the piston may be turned against the cutter 3, Fig. l, contraclockwise, and the device held to fixed position or piston held stationary and the device revolved clockwise around the piston for cutting material out of groove.

It will be seen in Fig. 5 that spring 1 as shown 40 in Fig. 1 is removed, also that in Fig. 6 spring 5 as shown in Fig. 1 is removed; the device may be used with either or both of the springs removed since their function is to make unnecessary any hand pressure directly against the cutter post for feeding into the material or for holding the cutter to any set horizontal position relative to the slide bar I.

Spring 5, as shown in Figures 1, 3, 4, and 5, respectively, around cutter post and engaging washer 6 and under face of cutter 3, is under compression and when the adjusting and the retaining nut 4, shown in Fig. 1 and other views, is backed-ofi the spring forces the cutter shaft and cutter higher above bar I; the spring thus holds bar. L s

It will be seen that the. relative clearance from .edge of the cutter to its heel, not contactingthe piston, may be increased or decreased by raising or lowering theme in position horizontally relative to. the handle portion of bar I, Fig. 1. This allows nicety'of adjustment for obtaining smoothness of operation and non-dig of tool. when used without spring 5 as shown in Fig. 6, the device is grasped in the hand to revolve same around the piston and finger and thumb are -applied to nut l and post 2 in order to hold the cutter to height adjusted cutting position.

When the device is used with longitudinal compresslonspring .1, intermediate to post 2, and retaining nut 8 fixed by pin 9 as on end of handle as shown in Fig. 1, feed of the cutter into the outthis spring and as shown in Fig. 5 it is necessary to produce longitudinal hand pressure 4 against the cutter shaft assembly to effect the cut within the scope of claims as herein made and as follows: i

I claim as my invention:

1. A piston ring groove scraper and deepenercomprising: a straight bar having one end bent back upon itself to form two spaced piston engaging points; a cutter post mounted on the straight portion of said bar slidable longitudinally of said bar along the straight portion of said bar and adjustably movable transversely of the bar, said post having a slot therein to receive said bar; a cutter on one end of said post arranged to engage the piston ring groove oppositely of said bent end of the bar a compression spring on said post between said bar and said cutter; and means on the other end of said post yieldingly held against said bar by said spring for retaining said post on said bar.

2. A piston ring groove scraper and deepener comprising: a straight bar having one end bent back upon itself to form two spaced piston engaging points; a cutter post mounted on the straight portion of said bar slidable longitudinally on said bar along the straight portion of said bar and movable transversely of the bar, said post having a slot therein to receive said bar; a cutter on one end of said post arranged to engage the piston ring groove oppositely of said bent end 5 of the bar; a compression spring on said post between said bar and said cutter; and a nut threaded on the other end of said post yieldingly held against said bar by said spring for retainlng' said post on said bar. I 1 3. A piston ringgroove scraper and deepener 7 comprising: a straight bar having one end bent back upon itself to form two spaced piston engaging points; a cutter post mounted on the straight portion of said bar slidable longitudinally of said 15 bar along the straight portion of said bar and movable transversely of the bar, said posthaving a slot therein to receive said bar; a cutter on said post arranged to engage the piston ring groove oppositely of said bent and of the bar; a com- 20 pression spring on said post between said bar and said cutter; means on.said post yieldingly held against said bar by said spring for retaining said post on said bar; a head on said bar; and a comsaid post having a slot therein to receive said bar,

a cutter on one end of said post arranged to en- 35 gage the piston ring groove oppositely of said bent end of the bar; an abutment member on the end of the straight portion of said bar; and a compression spring on said bar between said post and said abutment member. 40 5. A piston ring groove scraper and deepener comprising: a straight bar having one end bent back upon itself to form two spaced piston engaging points; a cutterpost mounted on the straight portion of said bar slidable longitudinally of said bar along the straight portion of said bar and adjustably movable transversely of the/ bar, said post having a slot therein to receive said bar; and a cutter on one end of said post arranged to engage the piston ring groove oppositely of said bent end of the bar.

CHARLES D. S'I'ROMGREN. 

